Coal mining; Technology; Development direction; Driveway; surrounding rock
1, current situation of coal mining in China.
Compared with foreign developed countries, China's coal mining technology is still backward. First, it is not high in mechanical and electrical integration, intelligence and automatic control technology; Second, there are still gaps in manufacturing technologies such as product reliability technology, digital integration technology and computer-aided design technology. Third, many small and medium-sized mines are still using blasting coal mining method, and the working face length is too short. Fourth, the degree of mechanization and work efficiency are low, and the technical equipment in coal mining mechanization system, transportation system, stope surrounding rock control system, roadway preparation system and auxiliary transportation system is generally insufficient; Fifth, China's coal mine professional and technical personnel are not connected, and the lack of technical personnel and low level make technical measures not in place, which restricts the safety technology and management level of coal mine production.
The continuous improvement and development of coal mining methods and technologies is the symbol of scientific progress in coal mining. At present, China, Russian and some European countries mainly adopt longwall mining method, while the United States and Australia mostly adopt short-wall mining method. With the rapid development of industry and information technology, China's coal mining technology has been continuously improved, the comprehensive mechanization ability has been greatly improved, the theory and technology of strata control have been gradually improved, and the safety and work efficiency of underground operation have also been greatly improved. In the near future, the application of microprocessor, computer and expert system, automation and robot mining technology will become a new underground coal mining system, thus replacing all manual and semi-automatic mining methods.
2. Development direction of coal mining in China.
2. 1 China's coal mining methods and technologies should be gradually improved.
High yield, high efficiency, high safety and high reliability are the development directions of modern coal mining methods and technologies. Combining modern high-tech, continuously developing powerful, efficient, safe, reliable, durable and intelligent coal mining equipment and production monitoring system, and gradually improving and perfecting coal mining technology are the basis for establishing China's characteristic coal mining technology theory. At present, China's longwall mining method has made some progress, and the application of top-coal caving mining and the research on mining methods and technologies with steep, unstable and complex geological structures are constantly improving and developing. Specific trends: First, develop high-efficiency and intensive production technology in coal mines and build high-yield and high-efficiency mining technology with highly concentrated production and high reliability, which should be gradually improved; Secondly, a set of modern mining technology with shallow depth, hard roof and hard coal seam with high yield and high efficiency has been developed, which has solved many mining technical problems; Third, the longwall mining technology in inclined thin coal seam, the overall support technology and efficient mining technology in thin coal seam face should be continuously improved; Fourth, we should gradually improve the support system of all kinds of fully mechanized mining equipment with high yield and high efficiency.
2.2 China's deep well mining technology needs further study.
Deep well mining usually refers to the mining technology used to mine coal from a specific depth on the surface. Its depth is determined according to the geological conditions at the root of coal seam. With the increasing demand for coal in society, the mining capacity and mining depth are also increasing, which is the inevitable trend of underground mining. Mine pressure control, rock burst prevention, gas and heat hazard control, deep well ventilation and roadway layout are all key technologies for deep well mining. Therefore, the development technology of deep mine should constantly analyze the characteristics of surrounding rock state, stress field and distribution state of deep mine, the change of working environment in deep mine workplace, the rapid excavation and support technology and equipment of deep mine roadway; The prevention and monitoring technology of rock burst in deep mines, the related supporting technology of high-yield and high-efficiency mining in deep mines, and the control technology and equipment of thermal damage in deep mines should be studied continuously and deeply.
2.3 Vigorously develop the "three under" coal mining technology
Mining under buildings, railways, water bodies and confined water bodies is referred to as "three down and one up" mining. Usually in the process of coal mine production, coal pillars are reserved under buildings, railways and water bodies, and no mining is carried out. With the increasing intensity and scope of coal mining in China, the problem of "three underground" coal mining is becoming more and more prominent, which not only leads to unreasonable mining in mines, but also causes a large backlog of coal resources. According to relevant data, China's coal pressure is137.9 billion. Therefore, it is an urgent problem for China's coal mining enterprises to deeply study the "three-under" mining technology, mine the "three-under" pressed coal, reduce the waste in mining areas and protect the mining environment. Coal mining enterprises should deeply study the law of mining overlying strata movement and surface subsidence, and study its rationality to meet the protection needs of surface, buildings and groundwater resources.
2.4 Continuously optimize roadway layout to reduce waste rock discharge.
Improving coal mine development and roadway layout and realizing reasonable centralized production are the technical development direction of coal mine production at present. Constantly optimizing roadway layout and reducing gangue discharge is a prerequisite for coal enterprises to obtain good technical and economic effects, which is of great strategic significance to the development of coal industry. Therefore, China coal mining enterprises should constantly improve and perfect the existing coal mining methods and mining layout. Continuously research and develop the expert system of roadway layout and the evaluation system of technology in coal mine geological conditions, so that the mining method and layout can be optimally matched with the geological conditions of coal seam. At the same time, focus on optimizing the development and deployment of high-yield and high-efficiency mines and roadway layout system, simplifying roadway layout, optimizing mining area and working face parameters, and studying the key technologies of centralized development, centralized coal preparation and centralized mining of single coal seam, greatly reducing the drivage rate of rock roadway, opening more coal roadway, reducing the output of gangue and maximizing mining benefits.
2.5 stope surrounding rock control technology
Surrounding rock control has always been an extremely important work in coal mine safety production. In recent years, with the continuous increase of mining depth, the number of all-coal roadway and soft rock roadway is increasing. The phenomenon of loose failure and large deformation of surrounding rock is becoming more and more common, which brings great harm to coal mining. Therefore, coal mines should vigorously study the surrounding rock control technology and theory suitable for deep large deformation mining, deeply study the application of high-tech and low-cost rock layer control technology under the conditions of hard roof and broken roof, the interaction mechanism between roof caving mining rock layer and support-surrounding rock, the support quality and roof dynamic monitoring technology, the prediction and prevention of rock burst, and develop new support equipment to ensure the safe, efficient and low-cost operation of coal mining.
2.6 underground coal gasification technology should be further promoted.
Underground coal gasification technology belongs to a special coal mining method, which is a new technology to control the combustion of underground coal, generate combustible gas through the heat and chemical action of coal, comprehensively develop clean energy and produce chemical raw materials. Its advantages are less investment, short construction period, quick effect, less labor, high efficiency, low cost and good benefit. It is very suitable for the complicated geological conditions and high proportion of inferior coal in China's coal mines. Therefore, coal mines should deeply popularize underground coal gasification technology, vigorously study and improve two typical underground coal gasification technologies, namely, "long passage, large section, two-stage" and "in-mine gasification", actively explore the technical ways to realize "two controls and three stabilities" and explore the ways to realize continuous and stable production.
Under the specific national conditions of severe coal pressure, the "Three Downs" has broad prospects for popularization and application. We will continue to study and improve two typical underground coal gasification processes, namely, "long passage, large cross section, two stages" and "mine gasification", carry out large-scale underground gasification experiments, explore technical approaches to realize "two controls and three stabilities", and realize continuous and stable production of coal mines.
3. Concluding remarks
Coal mining technology is an important symbol to measure a country's scientific and technological development level. With the new development of high-efficiency fully mechanized mining equipment in China, high-power electric traction shearer, heavy scraper conveyor, strong support of electrified hydraulic control system and large-capacity long-distance belt conveyor with advanced technology level are being vigorously promoted and applied, but the key technology of coal mining equipment is still the weak link in China. In order to narrow the gap with developed countries and promote the healthy, stable and efficient development of China's coal mining enterprises, it is necessary to carry out continuous research.
refer to
[1] Zhang Hongliang. China coal mining technology [J]. China new technology and new products, 20 10, 13.
Wei tong. Coal mining technology [J]. Sci-tech Journal, 20 10-03-29.
[3] Wang Qinghai. World coal mining [J]. Coal mine modernization 2008- 10-20.